Below is the screenshot of a passage from 'Oxford Guide to English Grammar by John Eastwood'.
The passage says A clause has a subject and a verb. Subject and Verb are the elements of a sentence or a clause. However, in the clause Our flight time will be approximately forty-five minutes there is another 'sentence element' which is complement which is other than the 'Subject' and 'Verb'. However, the passage says that 'there can be other phrases, too.' What is meant by 'other phrases, too' here? Does it mean other sentence elements, like complement? Or does it mean the types of phrases other than 'noun phrase' and 'verb phrase'. My main question is: In the examples of the clauses given in the passage, the clauses contain more than a 'subject' and 'verb'. They also have 'complement parts'. The 'complement' and 'verb' part of the example clauses have been shown to be separate or distinct. My second question is: Does the author clarify further in the passage that 'complement' can be part of a clause?
Wikipedia on this issue says:
In grammar, a clause is the smallest grammatical unit that can express a complete proposition. A typical clause consists of a subject and a predicate, where the predicate is typically a verb phrase – a verb together with any objects and other modifiers.
The above definition of the clause includes objects or complements in 'verb phrase'.